IBMF-2 (level 3) retained level 2, but the HHC asked subjects to provide symptom ratings when BG (blood glucose) was low and at an equal number of matching euglycemic readings. From these data, the HHC estimated a set of potentially significant symptoms of hypoglycemia for each individual, using an iterative algorithm following a previously published symptom significance estimation procedure. The patient manual for the HHC program is provided in supplementary data of published manuscript.